Предмет: Алгебра, автор: nastgri

Решите системы уравнений методом сложения:
x/5+y/6=-1/2
4x+7y=1

Ответы

Автор ответа: kulimby
1

4х + 7у = 1

( Х/5 ) + ( у/6 ) = - 1/2

Решение

( 6х + 5у )/30 = - 15/30

6х + 5у = - 15

4х + 7у = 1

4х = 1 - 7у

Х = 0,25 - 1,75у

6( 0,25 - 1,75у ) + 5у = - 15

1,5 - 10,5у + 5у = - 15

- 5,5у = - 16,5

у = 3

Х = 0,25 - 1,75•3 = 0,25 - 5,25 = - 5

Ответ ( - 5 ; 3 )

nastgri: спасибо, но только нужно писать что умножаешь на 30, а то я подумала что делишь.
kulimby: Простите пожалуйста....! Я учту это)))
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